Myself...I use a (now discontinued) TC electronics T2. It's got huge reverbs with modulation. It's not very subtle but I love it!
I love a little reverb thrown in as most have posted here; fretless, solo, ambient, textural, etc....
My newest reverb acquisition is the Neunaber Wet Version 5. After owning and trying tons of reverb pedals ranging from production to boutique, with all kinds of switches, profiles, knobs, features, etc., I wanted to simplify a bit.
The Neunaber is a super simple, absolutely gorgeous sounding reverb with two of the Neunaber algorithms installed that you can select via the knobs on the front; the classic Wet and the new W3T. The classic is a really nice "general purpose" reverb that has a little modulation and sounds fantastic. The new W3T is a bigger, deeper, lush, more modulated reverb that is hands down my favorite reverb that I've ever used/heard/experienced. The W3T has all those characteristics but the kicker is that it still sounds incredibly natural. It really is remarkable in my opinion. The audio quality of Neunaber products is pretty legendary and this unit is no exception. For me, it has been one of those inspirational pedals you run into every once in a while. Every time I kick it on, I find myself phrasing things a little differently, experimenting a little more, trying different inversions, etc. and I also look up and see that another 30-45 minutes has gone by.
I also own (and love!) the TC Electronics Trinity2 reverb. This is a more "special effects" reverb pedal and is not for the faint of heart! Massive, modulated, flanged, weird, textural, bordering on insane reverbs and the TC Electronic Toneprint capability as well. I love the T2 but I'm keeping it in reserve for those special occasions calling for something pretty dramatic!
The new Neunaber Wet V5 is on my board with the W3T algorithm selected.
Just my $.02 as usual.